The United States will send 560 more troops to Iraq later this year to help Iraqi forces in their efforts to retake Mosul from the militant group known as the Islamic State, US Defense Secretary Ash Carter said on Monday.

The announcement came during a visit to Baghdad, where Mr. Carter met US commanders along with Iraqi Prime Minister Haider al-Abadi and Defense Minister Khaled al-Obeidi. The increase in forces comes less than three months after US officials announced that they would dispatch about 200 more troops to accompany Iraqi forces advancing toward Mosul.

"With these additional US forces I'm describing today, we'll bring unique capability to the campaign and provide critical support to the Iraqi forces at a key moment in the fight," Carter told a gathering of US troops in Baghdad on Monday, as reported by Reuters.

Most of the new troops will work out of Qayara air base, about 40 miles from Mosul. The base had previously been under Islamic State control before it was recaptured by Iraqi forces with US military support, government forces said on Saturday. Prime Minister Abadi celebrated the recapture as a key step toward retaking Mosul, which is the militants' largest stronghold.

Carter stressed the strategic importance of Qayara while speaking to reporters, saying the airfield is "one of the hubs from which ... Iraqi security forces, accompanied and advised by us as needed, will complete the southernmost envelopment of Mosul."

Another senior US defense official described the base as "an important location for our advisers, for our fire support, working closely with the Iraqis and being closer to the fight."

The Islamic State has lost its grip on a number of territories in recent months, including the Syrian town of al-Shadadi in February, which was retaken by US-backed Syrian forces, and the recapture of Ramadi in December and Fallujah in June by Iraqi forces.

"While Iraqis mourn, again, analysts say the link between the Fallujah victory and the Baghdad bomb is a microcosm in Iraq of a broader phenomena," the Christian Science Monitor's Scott Petersen wrote following the bombing. "As the jihadist group loses ground in battlefields from Iraq and Syria to Libya, it is demonstrating that it can morph its tactics to conduct spectacular suicide attacks with conventional terrorist tools, from the heart of Europe to southern Asia."

While some have pointed to these attacks as a sign that the Islamic State is weakening and growing desperate, other experts say they actually signify the organization's ability to evolve and adapt as necessary.

"[I]t demonstrates (the Islamic State's) strength and long-term survival skills," Hassan Hassan, a resident fellow at the Tahrir Institute for Middle East Policy, writes for the New York Times. "The Islamic State has known for years that it would suffer setbacks and have to find ways to adapt...The threat is not going away."